Aircraft dynamic derivatives calculation using CFD techniques

Only the sum of aircraft pitching moment angle of attack (AOA) rate derivative and pitch rate derivative could be obtained by simulating the forced pitch oscillation using the unsteady flow numerical calculation method. But the dynamic stability analysis needs separate dynamic derivatives. To solve this problem, the sliding mesh was applied to simulate the forced pitch oscillation, and the sum of pitching moment AOA rate derivative and pitch rate derivative was obtained. Then the rotating reference frame was used to gain the pitching moment pitch rate derivative by simulating the steady climb movement. The rotating reference frame was also employed to acquire the rolling moment roll rate derivative by simulating the steady roll movement. The dynamic derivatives of a missile with cruciform tails and a seaplane were calculated. The results were consistent with experimental data, reference data and results acquired using other methods, indicating that this method could be used to calculate the dynamic derivatives of aircrafts with complicated configurations.